Coding on recyclable packaging is becoming an important consideration for manufacturers redesigning their packs to reduce waste and improve material recovery. Moving towards recyclable or mono-material packaging, however, affects much more than the packaging structure. It can also change how batch numbers, expiry dates, barcodes and 2D codes must be applied.
Films may become thinner, coatings may change and printing areas may react differently to ink, heat or laser energy. A coding technology that performed reliably on a conventional multilayer structure may therefore produce a different result on the new material.
For manufacturers, the challenge is clear: improve packaging recyclability while maintaining code quality, traceability and production efficiency.
What is mono-material packaging?
Mono-material packaging is predominantly made from one type of material, such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), paper or aluminium.
In flexible packaging, conventional structures often combine several materials to provide strength, printability and barrier protection. These layers can be difficult to separate during recycling. Mono-material structures are designed to simplify sorting and material recovery by reducing the number of incompatible components.
However, mono-material does not automatically mean recyclable. Recyclability also depends on factors such as:
- Local collection and recycling infrastructure.
- Adhesives, inks and coatings.
- Barrier layers and additives.
- Labels, sleeves and closures.
- Contamination from the packaged product.
- The overall design and composition of the pack.
Coding must therefore be considered as part of the complete packaging structure.
Why coding on recyclable packaging requires a different approach
Changes made to improve recyclability can affect the interaction between the packaging and the coding system.
A thinner flexible film, for example, may be more sensitive to heat or mechanical stress. A different coating can alter ink adhesion or laser contrast. Recycled content can also create variations in colour, texture and surface consistency.
The coding system must still produce information that remains clear and readable throughout manufacturing, transport, storage and retail. Depending on the application, this information may include:
- Batch or lot numbers.
- Manufacturing and expiry dates.
- Product identifiers.
- Barcodes and 2D codes.
- Serialised information.
- Traceability and recycling data.
Unreadable or incomplete codes can result in rejected products, manual rework, production waste and traceability risks. For this reason, packaging redesign and coding validation should form part of the same project.
How does the PPWR affect packaging coding?
The EU Packaging and Packaging Waste Regulation, or PPWR, is increasing the focus on packaging designed for recycling. The regulation introduces sustainability, labelling and recyclability requirements throughout the packaging lifecycle.
From 2030, packaging recyclability will be assessed using design-for-recycling criteria and recyclability performance grades. These requirements will affect companies placing packaging on the European market, including manufacturers based outside the EU.
The regulation does not prescribe one specific coding technology. Instead, companies need to evaluate whether every packaging component supports the intended recycling route. This includes inks, labels, ribbons, adhesives and other elements used to identify the product.
Manufacturers should consult the official EU Packaging and Packaging Waste Regulation and obtain specialist advice when assessing their individual compliance obligations.
Choosing a coding technology for recyclable packaging
There is no universal coding method for every recyclable or mono-material pack. The best option depends on the substrate, packaging design, required information, production speed and recycling route.
Laser coding
Laser coding creates information directly on the packaging surface without applying ink, labels or thermal-transfer ribbon. Depending on the substrate, it can produce permanent, high-contrast batch numbers, dates, text and machine-readable codes.
Eliminating coding consumables can reduce ribbon, cartridge and solvent waste. It can also simplify consumables management and reduce line interruptions associated with replacement.
Nevertheless, the laser wavelength, power, optics and marking parameters must be matched to the material. Testing is essential to ensure adequate contrast without compromising the integrity or barrier properties of the packaging.
Macsa id offers a range of laser marking solutions for packaging developed for materials including films, plastics, paper, cardboard, glass and metal.
Thermal transfer overprinting
Thermal transfer overprinting, or TTO, is widely used on flexible packaging. It provides good print quality and can accommodate variable information, but it requires thermal-transfer ribbons.
When assessing TTO for recyclable packaging, manufacturers should consider ribbon consumption, waste generation, downtime for ribbon changes and the compatibility of the transferred ink with the selected recycling stream.
Continuous inkjet and thermal inkjet
Inkjet systems can code a wide variety of packaging formats at industrial speeds. Their suitability depends on ink adhesion, drying time, contrast and resistance to moisture, oils, abrasion or temperature changes.
The ink formulation should also be assessed alongside the packaging material and its recycling requirements. Recycled-content substrates can show greater surface variation, making testing especially important.
Print and apply labelling
Print and apply systems provide consistent code quality on labels and are particularly useful for secondary and tertiary packaging. However, the label material and adhesive must be compatible with the recycling process intended for the main package.
In some applications, a direct code can reduce the need for an additional label. In others, a recycling-compatible label may still be the most suitable option.
Laser coding on mono-material flexible films
Flexible packaging presents one of the most demanding coding applications. Production lines operate at high speeds, while films can be thin, sensitive and exposed to oils, moisture or temperature variations.
UV laser technology can be particularly effective for certain recyclable and mono-material films. Instead of relying mainly on thermal interaction, UV wavelengths can create a photochemical reaction in compatible substrates or coatings. This can produce a precise, high-contrast mark with limited heat transfer to the surrounding material.
The Macsa id iLumiFlex UV laser coder is designed for coding flexible films, including mono-material and design-for-recycling structures. It can replace conventional TTO equipment in compatible applications and produce permanent codes without ink or ribbon.
Because film formulations and coatings vary, samples should always be tested before selecting the final laser configuration.
Five factors to evaluate before changing packaging
1. Material composition
Identify the base polymer, coating, barrier layer, colour and recycled content. Two films described as PE or PP can react very differently during coding.
2. Code content
Define whether the line needs simple text, an expiry date, a batch number, a QR code or a high-density GS1 DataMatrix. More complex codes require greater resolution and tighter process control.
3. Production conditions
Test the technology at the actual line speed and under realistic conditions. The result should also be assessed after filling, sealing, cooling, transport and storage.
4. Code verification
A code that looks acceptable to the human eye may still fail when scanned. Vision systems can confirm presence, position, content and readability directly on the production line.
5. Packaging integrity
The coding process must not weaken the material, damage a barrier layer or affect product protection. This is particularly important when working with thinner flexible films.
How coding supports more sustainable production
Sustainable packaging coding is not only about the recyclability of the final pack. It also concerns the resources consumed during production.
The right coding solution can help manufacturers:
- Reduce waste caused by unreadable or incorrect codes.
- Avoid unnecessary labels, ribbons or solvents.
- Minimise stoppages for consumable replacement.
- Reduce packaging discarded during line set-up.
- Maintain traceability throughout the supply chain.
- Apply variable 2D codes without using additional packaging elements.
These operational improvements should be measured using real production data. Packaging waste, consumable use, energy requirements, maintenance and code rejection rates should all form part of the assessment.
Testing is essential for recyclable packaging coding
Manufacturers should avoid selecting a coding technology based solely on the general name of a material. Surface treatments, pigments, coatings and production conditions can significantly affect the result.
A representative sample test can determine:
- The most appropriate coding technology.
- The correct wavelength, ink or ribbon.
- Achievable marking contrast.
- Maximum coding speed.
- Resistance to abrasion, moisture and chemicals.
- Barcode or 2D code readability.
- Any effect on packaging integrity.
This validation makes it possible to identify potential problems before introducing the material across a complete production line.
Preparing packaging lines for the next generation of materials
The shift towards recyclable and mono-material packaging will require closer collaboration between packaging developers, material suppliers, production teams and coding specialists.
Coding should be considered early in the packaging design process—not after the new material has already been approved. This allows brands to select an appropriate coding area, create sufficient contrast and validate the code under realistic conditions.
Macsa id helps manufacturers evaluate their substrates and choose the most suitable laser, inkjet or labelling technology for each application.
Is your new packaging ready for reliable coding?
Send us a sample of your recyclable or mono-material packaging. Our specialists can test the material and recommend a coding solution based on your code requirements, production speed and packaging format.